Unit 5 Chapter 1 Review When’s the Test?

1F – Describe the energy transfer during chemical reactions. 1. Endothermic reactions:. a. What is an endothermic reaction? Reactions that absorb ENERGY? Endo (entering) Thermic (heat) Needs a continual input of energy or the reaction stops!

Which plant had NO continual input of energy? Plant A Plant B

1F – Describe the energy transfer during chemical reactions. 1. Endothermic reactions: b. Which is greater in an endothermic reaction – the stored chemical energy (“SCE”) of the reactants or the stored chemical energy of the products? Why? The SCE of the products is greater than the SCE of the reactants. For energy to be conserved, energy is transferred INTO the system and the SCE of the system increases. The SCE of the products is greater than the SCE of the reactants. For energy to be conserved, energy is transferred INTO the system and the SCE of the system increases.

Which has more stored chemical energy? Reactants or Products?

1F – Describe the energy transfer during chemical reactions. 1. Endothermic reactions: c. What change will occur in an endothermic reaction? In an endothermic reaction, energy is transferred into the system and the stored chemical energy of the system increases. In an endothermic reaction, energy is transferred into the system and the stored chemical energy of the system increases. Observations include heat entering the system. Observations include heat entering the system.

1F – Describe the energy transfer during chemical reactions. 2. Exothermic reactions: a. What is an exothermic reaction? A chemical reaction that Produces energy. Exo – Exits or leaves Thermic – heat Once the reaction is started by activation energy (like a spark or match) there is NO stopping this type of reaction!

The SCE of the reactants is greater than the SCE of the products. The SCE of the reactants is greater than the SCE of the products. 1F – Describe the energy transfer during chemical reactions. 2. Exothermic reactions: b. Which is greater in an exothermic reaction – the SCE of the reactants or the SCE of the products? Why?

Exothermic Reactant-Product Diagram Which has more stored chemical energy? Reactants and Products?

1F – Describe the energy transfer during chemical reactions. 2. Exothermic reactions: c. What change will we observe in an exothermic reaction? Energy is transferred out of the system and the SCE of the system decreases. Observations include heat energy exiting the system. Energy is transferred out of the system and the SCE of the system decreases. Observations include heat energy exiting the system.

1A – Identify chemical & physical interactions and support with evidence. 3. What is the difference between a physical interaction and a chemical interaction? In a physical interaction the reactants and products don’t change. There is no evidence anything new has been created as in a chemical interaction. In a physical interaction the reactants and products don’t change. There is no evidence anything new has been created as in a chemical interaction. A chemical interaction is any type of interaction that results in at least ONE new material. A chemical interaction is any type of interaction that results in at least ONE new material.

Which one of these is a physical interaction or chemical interaction?

1A – Identify chemical & physical interactions and support with evidence. 4. What are some common chemical interactions (reactions)? Disappearance of one of the original materials Disappearance of one of the original materials Appearance of a material in a different phase* (at room temperature) Appearance of a material in a different phase* (at room temperature) Changes in other properties (like color, odor, texture, density, hardness, size or shape, interaction with water (dissolve or doesn’t dissolve), flammability, reaction with acid-base indicators Changes in other properties (like color, odor, texture, density, hardness, size or shape, interaction with water (dissolve or doesn’t dissolve), flammability, reaction with acid-base indicators *Phase means solid, liquid or gas

What do the circles mean? What is he breathing into the bag? These are ALL phases of matter

1B – Describe and classify materials according to their properties. 5. Is one property of a material always enough to identify the material? Why or why not? No. Different materials are identified by a unique set of properties. Characteristics properties are more useful for identifying unknown substances than properties like shape, mass, volume or texture. No. Different materials are identified by a unique set of properties. Characteristics properties are more useful for identifying unknown substances than properties like shape, mass, volume or texture. Characteristic properties like melting and boiling points and density. Characteristic properties like melting and boiling points and density.

1B– Dscribe and classify materials according to their properties. 7. Use the Table of Density and Melting Point and Boiling Point to describe the properties of a substance of your choosing. On your own

What is the freezing and melting point for water? Why is this a characteristic property?

1C– Determine whether a substance is an acid, base, or neutral using physical & chemical properties. Discuss strength based on the pH scale.. 8. Describe a neutralization reaction. What are the reactants? What are the products? Any reaction between an acid and a base is called neutralization leaving a solution less acidic or basic than the original acid or base. Any reaction between an acid and a base is called neutralization leaving a solution less acidic or basic than the original acid or base. Reactants: Acid + Base Reactants: Acid + Base Products: Salt + water Products: Salt + water

How would this happen?

1C– Determine whether a substance is an acid, base, or neutral using physical & chemical properties. Discuss strength based on the pH scale.. 9. How can you tell if something is an acid, base, or neutral? Acid-base indicators are compounds (dye) that change color in an acid, base, or both an acid or base. Ex: BTB or BTY Acid-base indicators are compounds (dye) that change color in an acid, base, or both an acid or base. Ex: BTB or BTY Look at their characteristic properties Look at their characteristic properties Hmmm..what are their characteristic properties? Hmmm..what are their characteristic properties?

1C– Determine whether a substance is an acid, base, or neutral using physical & chemical properties. Discuss strength based on the pH scale How can you measure the pH number of a substance? Specially coated paper called Specially coated paper called Universal-coated paper or a pH meter will measure the pH number on the scale. Universal-coated paper or a pH meter will measure the pH number on the scale.

1C– Determine whether a substance is an acid, base, or neutral using physical & chemical properties. Discuss strength based on the pH scale What are the pH numbers of acids, bases, and neutral substances?

1D– Identify the reactants and products in a chemical reaction. Describe the evidence for a chemical reaction. 12. What do the terms “reactant” and “product” mean? Reactant: original materials in an interaction Reactant: original materials in an interaction Product: New materials created from an interaction. Product: New materials created from an interaction. What would be the reactant and product in a burning candle?

1E– Give evidence to support the law of conservation of mass during chemical reactions. 13. What is the Law of Conservation of Mass? The Law of Conservation* of Mass states that in a closed mass system (a system with no mass inputs and mass outputs) the mass of the system does not change during interactions. The Law of Conservation* of Mass states that in a closed mass system (a system with no mass inputs and mass outputs) the mass of the system does not change during interactions. *What does it mean to conserve something?

1E– Give evidence to support the law of conservation of mass during chemical reactions. 14. What is a closed system and how does it relate to the law? A closed mass system (a system with no mass inputs and mass outputs) the mass of the system does not change during interactions. A closed mass system (a system with no mass inputs and mass outputs) the mass of the system does not change during interactions. Is a tree planted outside in an open or closed system? Why?

The End Study your lab notebook Study your lab notebook Study your Activity Summaries Study your Activity Summaries Study quizzes Study quizzes Study!!! Study!!! When is the test? When is the test?